Temperature change rate controllable deep hypothermia environment test device and test method

Abstract

The invention relates to the technical field of spacecraft ground tests, in particular to a temperature change rate controllable deep hypothermia environment test device and a test method, the temperature change rate controllable deep hypothermia environment test device comprises an environment simulation container, a liquid nitrogen radiation heat exchanger, a gas helium radiation heat exchanger, a gas helium supply assembly, a vacuum pump set and a temperature control board; and the cold trap heat exchanger can purify helium, so that the cooling rate can be more accurately controlled. When the current temperature of the test piece is greater than the target temperature, the flow of helium flowing into the environment simulator is controlled by controlling the opening degree of the first helium compensation valve, and the convective heat exchange intensity in the environment simulation container can be changed in cooperation with the adjustment of the pressure in the environment simulation container, so that the cooling rate is increased or reduced; therefore, the purpose of accurately controlling the cooling rate is achieved. And when the current temperature of the test piece is smaller than the target temperature and the current pressure is smaller than or equal to 10 <-3 > pa, the test piece is properly heated through the temperature control plate so as to accurately control the temperature of the test piece.

Description

Technical Field

[0001] The present invention relates to the technical field of spacecraft ground tests, and in particular to a deep low temperature environment test device with controllable temperature change rate and a test method. Background Art

[0002] The lunar surface is an extreme high and low temperature environment, and the lunar day and lunar night last up to 15 days. Probes working on the lunar surface often need to withstand a low temperature environment of -200°C or below for about 15 days at night. Therefore, it is necessary to verify the performance of various moving parts on the probe in a ground simulation environment. In ground tests, a variety of vacuum pumps are generally used to form a vacuum environment of the order of 0.001Pa, and a low temperature background of 100K is initially formed through a liquid nitrogen radiation heat exchanger, and a deep low temperature background of 40K is further achieved through the compression-expansion of helium.

[0003] When the temperature of the test piece is lower than 100K, the cooling rate will be greatly reduced. When the background temperature is 40K, the cooling rate of the test piece at 80K is only about 5% of that at 160K. Therefore, the subsequent cooling time of the test piece can often reach several days or even more than a week. At present, although there is a method of combining liquid nitrogen and helium to construct a deep low temperature background, which helps to increase the cooling rate. However, the cooling rate of the test piece still cannot be controlled more accurately.

[0004] Therefore, how to more accurately control the cooling rate of the test piece becomes a technical problem that needs to be solved urgently by those skilled in the art. Summary of the invention

[0005] The invention provides a deep low temperature environment test device and a test method with controllable temperature change rate, which are used to solve the problem of how to more accurately control the temperature drop rate of a test piece.

[0006] In one aspect, the present invention provides a deep low temperature environment test device with controllable temperature change rate, comprising:

[0007] Environmental simulation container;

[0008] The liquid nitrogen radiation heat exchanger is installed in the environment simulation container and can reduce the temperature in the environment simulation container to below 100K;

[0009] The gas helium radiation heat exchanger is arranged in the liquid nitrogen radiation heat exchanger, and a test chamber is formed inside; the temperature in the test chamber can be reduced to below 40K;

[0010] A helium supply assembly includes a helium storage tank, a cold trap heat exchanger, a helium compressor, a helium expander and a first helium compensation valve; the helium storage tank, the cold trap heat exchanger, the helium compressor, the helium expander and the test chamber are connected in sequence; one end of the first helium compensation valve is connected to the cold trap heat exchanger, and the other end is connected to the interior of the environmental simulation container;

[0011] A vacuum pump group, which can be connected to the environment simulation container to evacuate the environment simulation container;

[0012] The temperature control board is arranged in the test chamber; the test piece is installed on the temperature control board.

[0013] In some embodiments, the cold trap heat exchanger is provided with a first cryogenic medium inlet, a first cryogenic medium outlet, a helium inlet and a helium outlet; the helium inlet is connected to the helium storage tank; the helium outlet is connected to the first helium compensation valve;

[0014] The helium compressor is provided with a second cryogenic working medium inlet, a second cryogenic working medium outlet, a first cryogenic low-pressure helium inlet and a normal temperature high-pressure helium outlet; the first cryogenic low-pressure helium inlet can be connected to the helium outlet;

[0015] The helium expander is provided with a low-temperature and high-pressure helium inlet and a first low-temperature and low-pressure helium outlet; the first low-temperature and low-pressure helium outlet is connected to the test chamber;

[0016] The helium supply kit also includes:

[0017] The helium heat exchanger is provided with a second low-temperature and low-pressure helium inlet, a second low-temperature and low-pressure helium outlet, a normal-temperature and high-pressure helium inlet and a low-temperature and high-pressure helium outlet; the second low-temperature and low-pressure helium inlet is connected to the test chamber; the second low-temperature and low-pressure helium outlet is connected to the first low-temperature and low-pressure helium inlet; the normal-temperature and high-pressure helium inlet is connected to the normal-temperature and high-pressure helium outlet; the low-temperature and high-pressure helium outlet is connected to the low-temperature and high-pressure helium inlet.

[0018] In some embodiments, the helium supply assembly further comprises:

[0019] The second helium compensation valve has one end connected to the helium outlet and the other end connected to the first low-temperature and low-pressure helium inlet.

[0020] In some embodiments, the helium supply assembly further comprises:

[0021] A helium recovery valve has one end connected to the second low-temperature and low-pressure helium outlet and the other end connected to the helium storage tank.

[0022] In some embodiments, the temperature control panel includes:

[0023] a substrate with the test piece mounted on the top surface;

[0024] A thin film electric heater mounted on the substrate;

[0025] Heat detection sensor, suitable for installation on the test piece.

[0026] In some embodiments, it also includes:

[0027] Monitor, installed in the test chamber;

[0028] The reflector is installed in the test chamber; the monitor monitors the test piece through the reflector.

[0029] On the other hand, the present invention also provides a deep low temperature environment test method with controllable temperature change rate, comprising:

[0030] Use a liquid nitrogen radiation heat exchanger to reduce the temperature inside the environmental simulation container to below 100K;

[0031] Reduce the temperature in the test chamber of the gas-helium radiation heat exchanger to below 40K;

[0032] Use a vacuum pump set to evacuate the environmental simulation container;

[0033] Get the current temperature of the test piece. If the current temperature is equal to the target temperature, maintain the current temperature for a preset time. If the current temperature is greater than the target temperature, calculate the current cooling rate based on the current temperature. If the current temperature is less than the target temperature, get the current pressure in the environmental simulation container.

[0034] In some of the embodiments, if the current cooling rate is less than 0.5 K / min, the opening of the first helium compensation valve is increased; if the current cooling rate is greater than 1.5 K / min, the opening of the first helium compensation valve is reduced; if the current cooling rate is between 0.5 K / min-1.5 K / min, the opening of the first helium compensation valve is maintained.

[0035] In some embodiments, if the current pressure is less than or equal to 10 -3 pa, adjust the heating power of the temperature control board; if the current pressure is greater than 10 -3 When pa, close the first helium compensation valve and use the vacuum pump group to continue to evacuate the environmental simulation container.

[0036] The beneficial effects of the present invention are as follows: The cryogenic environmental test device with controllable temperature change rate of the present invention is equipped with a liquid nitrogen radiation heat exchanger, which can reduce the temperature in the environmental simulation container to below 100K. The temperature in the test chamber of the helium radiation heat exchanger can be reduced to below 40K. Adding a cold trap heat exchanger to create a low-temperature environment allows impurity gases that are prone to condensation at low temperatures to separate from the helium, which is conducive to more accurate control of the cooling rate and reduces the possibility of failure of components of the cryogenic environmental test device with controllable temperature change rate. The helium compressor can convert helium in a low-temperature and low-pressure state into helium in a normal-temperature and high-pressure state. The helium expander can convert helium in a low-temperature and high-pressure state into helium in a low-temperature and low-pressure state, and continuously replenish low-temperature and low-pressure helium into the test chamber so that the temperature in the test chamber can be reduced to below 40K. When the current temperature of the test piece is greater than the target temperature, the flow of helium into the environmental simulator is controlled by controlling the opening of the first helium compensation valve. By adjusting the pressure in the environmental simulation container, the intensity of convective heat transfer in the environmental simulation container can be changed to strengthen or weaken the heat transfer effect, thereby increasing or reducing the cooling rate, thereby achieving the purpose of accurately controlling the cooling rate. The vacuum pump group can evacuate the environmental simulation container so that the internal pressure of the environmental simulator is less than or equal to 10 -3 When the current temperature of the test piece is lower than the target temperature and the current pressure is lower than or equal to 10 -3 When pa, the test piece is appropriately heated by the temperature control board to accurately control the temperature of the test piece. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] Figure 1 It is a schematic structural diagram of some specific embodiments of a deep low temperature environment test device with controllable temperature change rate according to the present invention;

[0038] Figure 2 It is a flow chart of some specific embodiments of a deep low temperature environment test method with controllable temperature change rate of the present invention.

[0039] In the accompanying drawings, 110, environmental simulation container; 120, liquid nitrogen radiation heat exchanger; 130, gas helium radiation heat exchanger; 140, temperature control board; 151, helium storage tank; 152, cold trap heat exchanger; 153, helium compressor; 154, helium expander; 155, helium heat exchanger; 156, second helium compensation valve; 157, first helium compensation valve; 158, helium recovery valve; 160, vacuum pump group; 170, reflector; 180, monitor; 200, test piece. DETAILED DESCRIPTION

[0040] The technical solution of the present invention will be clearly and completely described below in conjunction with the embodiments. Obviously, the described embodiments are part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0041] As described in the background technology, when the temperature of the test piece is lower than 100K, the cooling rate will be greatly reduced. When the background temperature is 40K, the cooling rate of the test piece at 80K is only about 5% of that at 160K. Therefore, the subsequent cooling time of the test piece can often reach several days or even more than a week. At present, although there is a method of combining liquid nitrogen and helium gas to construct a deep low temperature background, it is helpful to increase the cooling rate. However, the cooling rate of the test piece still cannot be controlled more accurately. Therefore, how to more accurately control the cooling rate of the test piece has become a technical problem that needs to be solved urgently by those skilled in the art.

[0042] To solve the above problems, refer to Figure 1On the one hand, the present invention provides a cryogenic environmental test device with controllable temperature change rate, including an environmental simulation container 110, a liquid nitrogen radiation heat exchanger 120, a gas helium radiation heat exchanger 130, a gas helium supply assembly, a vacuum pump group 160 and a temperature control board 140. The environmental simulation container 110 provides a cryogenic environmental test site. The liquid nitrogen radiation heat exchanger 120 is arranged in the environmental simulation container 110, and can reduce the temperature in the environmental simulation container 110 to below 100K. The gas helium radiation heat exchanger 130 is arranged in the liquid nitrogen radiation heat exchanger 120, and a test cavity is formed inside. The test cavity is connected to the inside of the environmental simulation container 110. The temperature in the test cavity can be reduced to below 40K. The gas helium supply assembly includes a helium storage tank 151, a cold trap heat exchanger 152, a helium compressor 153, a helium expander 154 and a first helium compensation valve 157. The helium storage tank 151, the cold trap heat exchanger 152, the helium compressor 153, the helium expander 154 and the test chamber are connected in sequence. The helium storage tank 151 is used to store gas helium. Since gas helium may be mixed with other impurity gases such as water vapor and carbon dioxide during long-term storage, and these impurity gases are prone to form frost layers in a deep low temperature environment to affect heat exchange, and may also form ice crystals that fall into the helium expander 154, causing damage to the helium expander 154. Therefore, adding a cold trap heat exchanger 152 to create a low-temperature environment, so that the impurity gases that are easy to condense at low temperatures are separated from the helium, it is conducive to more accurately controlling the cooling rate and reducing the possibility of failure of components of the deep low temperature environment test device with controllable temperature change rate. The helium compressor 153 can convert helium in a low-temperature and low-pressure state into helium in a normal temperature and high-pressure state. The helium expander 154 can convert helium in a low-temperature and high-pressure state into helium in a low-temperature and low-pressure state, and continuously replenish low-temperature and low-pressure helium into the test chamber so that the temperature in the test chamber can be reduced to below 40K. One end of the first helium compensation valve 157 is connected to the cold trap heat exchanger 152, and the other end is connected to the interior of the environmental simulation container 110. When the current temperature of the test piece 200 is greater than the target temperature, the flow of helium flowing into the environmental simulator is controlled by controlling the opening of the first helium compensation valve 157. In conjunction with the adjustment of the pressure in the environmental simulation container 110, the convective heat exchange intensity in the environmental simulation container 110 can be changed, and the heat exchange effect can be strengthened or weakened to increase or decrease the cooling rate, thereby achieving the purpose of accurately controlling the cooling rate. The vacuum pump group 160 can be connected to the environmental simulation container 110 to evacuate the environmental simulation container 110, which can make the internal pressure of the environmental simulator less than or equal to 10 -3 pa. The temperature control board 140 is arranged in the test chamber. A test piece 200 to be subjected to a deep low temperature test is mounted on the temperature control board 140. The test piece 200 may be a motor for a spacecraft, an unfolding structure, etc. When the current temperature of the test piece 200 is lower than the target temperature and the current pressure is lower than or equal to 10 -3 When pa, the test piece 200 is appropriately heated by the temperature control plate 140 to accurately control the temperature of the test piece 200.

[0043] Specifically, in the exemplary embodiment, the cold trap heat exchanger 152 is provided with a first cryogenic working fluid inlet, a first cryogenic working fluid outlet, a helium inlet and a helium outlet. The helium inlet is connected to the helium storage tank 151. The helium outlet is connected to the first helium compensation valve 157. The first cryogenic working fluid flows into the cold trap heat exchanger 152 from the first cryogenic working fluid inlet, and flows out of the cold trap heat exchanger 152 from the first cryogenic working fluid outlet, so as to achieve the purpose of cooling the helium flowing through the cold trap heat exchanger 152, and then remove the impurity gas mixed in the helium. The first cryogenic working fluid can be liquid nitrogen or cryogenic gas helium, which can cool the cold trap heat exchanger 152 to below 100K. The helium compressor 153 is provided with a second cryogenic working fluid inlet, a second cryogenic working fluid outlet, a first low-temperature low-pressure helium inlet and a normal temperature high-pressure helium outlet. The first low-temperature low-pressure helium inlet can be connected to the helium outlet. The second cryogenic working fluid flows into the helium compressor 153 from the second cryogenic working fluid inlet, and flows out of the helium compressor 153 from the second cryogenic working fluid outlet, so as to achieve the purpose of cooling the helium compressor 153. The helium compressor 153 is water-cooled, and the second cryogenic working fluid is cooling water. With the assistance of cooling water, the helium compressor 153 realizes constant temperature compression, and converts the low-temperature and low-pressure helium into normal temperature and high-pressure helium. The helium expander 154 is provided with a low-temperature and high-pressure helium inlet and a first low-temperature and low-pressure helium outlet. The first low-temperature and low-pressure helium outlet is connected to the test chamber. The helium supply assembly also includes a helium heat exchanger 155, a second helium compensation valve 156 and a helium recovery valve 158. The helium heat exchanger 155 is provided with a second low-temperature and low-pressure helium inlet, a second low-temperature and low-pressure helium outlet, a normal temperature and high-pressure helium inlet and a low-temperature and high-pressure helium outlet. The second low-temperature and low-pressure helium inlet is connected to the test chamber. The second low-temperature and low-pressure helium outlet is connected to the first low-temperature and low-pressure helium inlet. The normal temperature and high-pressure helium inlet is connected to the normal temperature and high-pressure helium outlet. The low temperature and high pressure helium outlet is connected to the low temperature and high pressure helium inlet. One end of the second helium compensation valve 156 is connected to the helium outlet, and the other end is connected to the first low temperature and low pressure helium inlet. One end of the helium recovery valve 158 is connected to the second low temperature and low pressure helium outlet, and the other end is connected to the helium storage tank 151. The helium from the helium storage tank 151 flows into the cold trap heat exchanger 152 through the helium inlet, and after purification, flows out of the cold trap heat exchanger 152 from the helium outlet. Afterwards, the purified helium can flow into the environmental simulation container 110 through the first helium compensation valve 157, or flow into the helium compressor 153 through the second helium compensation valve 156 and the first low-temperature and low-pressure helium inlet to be compressed into normal temperature and high-pressure helium. The normal temperature and high-pressure helium flows out of the helium compressor 153 from the normal temperature and high-pressure helium outlet, and flows into the helium heat exchanger 155 through the normal temperature and high-pressure helium inlet for preliminary cooling. The cooled helium flows out of the helium heat exchanger 155 from the low-temperature and high-pressure helium outlet in a low-temperature and high-pressure state, and flows into the helium expander 154 through the low-temperature and high-pressure helium inlet. The helium expander 154 uses a turbine expansion method to achieve adiabatic expansion of the helium, so as to further cool the helium and make the temperature of the helium reach about 20K.Afterwards, helium with a temperature of about 20K is input into the test chamber. The helium with a temperature of about 40K in the test chamber can flow into the helium heat exchanger 155 through the second low-temperature and low-pressure helium inlet, and flow into the helium compressor 153 through the second low-temperature and low-pressure helium outlet and the first low-temperature and low-pressure helium inlet to be used again. When the helium with a temperature of about 40K flowing out of the test chamber flows through the helium heat exchanger 155, its cold capacity can be recycled, thereby improving the cold utilization rate. When it is necessary to replenish the helium cycle refrigeration system with helium, the second helium compensation valve 156 can be opened. After the test is completed, the helium recovery valve 158 can be opened to recover the helium to the helium storage tank 151 for standby use. It should be pointed out that the helium recovery valve 158 is a one-way valve to prevent backflow.

[0044] Preferably, the liquid nitrogen radiation heat exchanger 120 is a tube-fin type or honeycomb air expansion plate type radiation heat exchanger, the surface of which is coated with black paint with high emissivity and high absorption. Liquid nitrogen flows inside it to simulate a low-temperature radiation background below 100K.

[0045] Preferably, the specific structure of the gas-helium radiation heat exchanger 130 is similar to that of the liquid nitrogen radiation heat exchanger 120, and contains deep-cryogenic helium gas to simulate a deep-cryogenic radiation background below 40K.

[0046] Preferably, the vacuum pump group 160 includes a positive displacement vacuum pump, a cryogenic pump, and a turbomolecular pump, etc., which can be used in combination to make the pressure in the environment simulation container 110 equal to or lower than 10 -3 pa.

[0047] Preferably, the temperature control board 140 includes a substrate, a thin film electric heater and a heat detection sensor. A test piece 200 is mounted on the top surface of the substrate. The substrate is made of metal and has good thermal conductivity. The thin film electric heater is mounted on the substrate by pasting, and the heat exchange intensity between the temperature control board 140 and the test piece 200 can be adjusted by adjusting the heating power. The heat detection sensor is suitable for being mounted on the test piece 200 to detect the temperature of the test piece 200.

[0048] The deep low temperature environment test device with controllable temperature change rate also includes a monitor 180 and a reflector 170. The monitor 180 is installed in the test chamber. The monitor 180 is a camera with a vacuum low temperature protection tooling. The vacuum low temperature protection tooling provides a normal temperature and pressure environment for the camera to ensure the normal operation of the camera. The vacuum low temperature protection tooling includes a metal shell and a multi-layer heat insulation layer coated outside the metal shell. The reflector 170 is installed in the test chamber. The monitor 180 monitors the test piece 200 through the reflector 170 to prevent the heat radiation generated by the glass window from interfering with the cooling process of the test piece 200.

[0049] Reference Figure 2On the other hand, the present invention also provides a deep low temperature environment test method with controllable temperature change rate, comprising:

[0050] First, S100, a liquid nitrogen radiation heat exchanger is used to reduce the temperature inside the environment simulation container to below 100K.

[0051] Then, S200, the temperature in the test chamber of the gas-helium radiation heat exchanger is lowered to below 40K.

[0052] Next, at S300 , a vacuum pump set is used to evacuate the environment simulation container.

[0053] Then, S400, the current temperature of the test piece is obtained. If the current temperature is equal to the target temperature, the current temperature is maintained for a preset time. If the current temperature is greater than the target temperature, the current cooling rate is calculated based on the current temperature. If the current temperature is less than the target temperature, the current pressure in the environmental simulation container is obtained.

[0054] It should be noted that each temperature control cycle is 1-6 seconds. The current cooling rate is calculated based on the temperature detected in the current temperature control cycle, the temperature detected in the previous temperature control cycle, and the duration.

[0055] S510: If the current cooling rate is less than 0.5K / min, increase the opening of the first helium compensation valve. If the current cooling rate is greater than 1.5K / min, reduce the opening of the first helium compensation valve. If the current cooling rate is between 0.5K / min-1.5K / min, maintain the opening of the first helium compensation valve.

[0056] S520, if the current pressure is less than or equal to 10 -3 pa, adjust the heating power of the temperature control board. If the current pressure is greater than 10 -3 When pa, close the first helium compensation valve and use the vacuum pump group to continue to evacuate the environmental simulation container.

[0057] It should be noted that by adjusting the heating power of the temperature control plate, the heating rate can be adjusted to properly heat the test piece. -3 pa, continue to evacuate the environment simulation container using the vacuum pump group until the pressure in the environment simulation container is less than or equal to 10 -3 pa, and then adjust the heating power of the temperature control plate.

[0058] By adopting the above method, when the current temperature of the test piece is greater than the target temperature, the flow rate of helium flowing into the environmental simulator is controlled by controlling the opening of the first helium compensation valve. In combination with the adjustment of the pressure in the environmental simulation container, the convective heat transfer intensity in the environmental simulation container can be changed, and the heat exchange effect can be strengthened or weakened to increase or decrease the cooling rate, thereby achieving the purpose of accurately controlling the cooling rate.

[0059] In the description of the present invention, it is to be understood that the terms “center”, “longitudinal”, “lateral”, “length”, “width”, “thickness”, “up”, “down”, “front”, “back”, “left”, “right”, “vertical”, “horizontal”, “top”, “bottom”, “inside”, “outside”, “clockwise”, “counterclockwise”, “axial”, “radial”, “circumferential”, etc., indicating orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as limiting the present invention.

[0060] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In the description of the present invention, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0061] In the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral one; it can be a mechanical connection, an electrical connection, or communication with each other; it can be a direct connection, or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0062] In the present invention, the terms "one embodiment", "some embodiments", "examples", "specific examples", or "some examples" etc. mean that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the described specific features, structures, materials or characteristics may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction.

[0063] Although the embodiments of the present invention have been shown and described above, it is to be understood that the above embodiments are exemplary and are not to be construed as limitations of the present invention. A person skilled in the art may change, modify, replace and vary the above embodiments within the scope of the present invention.

Claims

1. A deep low temperature environment test device with controllable temperature change rate, characterized in that: include: Environmental simulation container; A liquid nitrogen radiation heat exchanger is disposed in the environmental simulation container and is capable of reducing the temperature in the environmental simulation container to below 100K; A gas-helium radiation heat exchanger is arranged in the liquid nitrogen radiation heat exchanger, and a test chamber is formed inside the test chamber; the temperature in the test chamber can be reduced to below 40K; A helium supply assembly, comprising a helium storage tank, a cold trap heat exchanger, a helium compressor, a helium expander and a first helium compensation valve; the helium storage tank, the cold trap heat exchanger, the helium compressor, the helium expander and the test chamber are connected in sequence; one end of the first helium compensation valve is connected to the cold trap heat exchanger, and the other end is connected to the interior of the environmental simulation container; A vacuum pump group, which can be connected to the environment simulation container to evacuate the environment simulation container; A temperature control panel is arranged in the test chamber; A test piece is installed on the temperature control board.

2. The deep low temperature environment test device with controllable temperature change rate according to claim 1, characterized in that: The cold trap heat exchanger is provided with a first cryogenic medium inlet, a first cryogenic medium outlet, a helium inlet and a helium outlet; the helium inlet is connected to the helium storage tank; the helium outlet is connected to the first helium compensation valve; The helium compressor is provided with a second cryogenic working medium inlet, a second cryogenic working medium outlet, a first low-temperature low-pressure helium inlet and a normal-temperature high-pressure helium outlet; The first low-temperature and low-pressure helium inlet can be communicated with the helium outlet; The helium expander is provided with a low-temperature and high-pressure helium inlet and a first low-temperature and low-pressure helium outlet; The first low-temperature and low-pressure helium outlet is connected to the test chamber; The helium supply assembly also includes: A helium heat exchanger is provided with a second low-temperature and low-pressure helium inlet, a second low-temperature and low-pressure helium outlet, a normal-temperature and high-pressure helium inlet, and a low-temperature and high-pressure helium outlet; The second low-temperature and low-pressure helium inlet is connected to the test chamber; the second low-temperature and low-pressure helium outlet is connected to the first low-temperature and low-pressure helium inlet; the normal temperature and high-pressure helium inlet is connected to the normal temperature and high-pressure helium outlet; the low-temperature and high-pressure helium outlet is connected to the low-temperature and high-pressure helium inlet.

3. The deep low temperature environment test device with controllable temperature change rate according to claim 2, characterized in that: The helium supply assembly also includes: A second helium compensation valve has one end connected to the helium outlet and the other end connected to the first low-temperature and low-pressure helium inlet.

4. The deep low temperature environment test device with controllable temperature change rate according to claim 2, characterized in that: The helium supply assembly also includes: A helium recovery valve has one end connected to the second low-temperature and low-pressure helium outlet and the other end connected to the helium storage tank.

5. The deep low temperature environment test device with controllable temperature change rate according to any one of claims 1 to 4, characterized in that: The temperature control panel comprises: a substrate, the test piece being mounted on the top surface; A thin film electric heater is mounted on the substrate; The heat detection sensor is suitable for being installed on the test piece.

6. The deep low temperature environment test device with controllable temperature change rate according to any one of claims 1 to 4, characterized in that: Also includes: A monitor installed in the test chamber; A reflector, installed in the test chamber; The monitor monitors the test piece through the reflective plate.

7. A deep low temperature environment test method with controllable temperature change rate, characterized in that: include: Use a liquid nitrogen radiation heat exchanger to reduce the temperature inside the environmental simulation container to below 100K; Reduce the temperature in the test chamber of the gas-helium radiation heat exchanger to below 40K; Using a vacuum pump set to evacuate the environment simulation container; Obtaining the current temperature of the test piece, and if the current temperature is equal to the target temperature, maintaining the current temperature for a preset time period; If the current temperature is greater than the target temperature, the current cooling rate is calculated according to the current temperature; if the current temperature is less than the target temperature, the current pressure in the environmental simulation container is obtained.

8. The deep low temperature environment test method with controllable temperature change rate according to claim 7, characterized in that: If the current cooling rate is less than 0.5K / min, the opening of the first helium compensation valve is increased; if the current cooling rate is greater than 1.5K / min, the opening of the first helium compensation valve is reduced; if the current cooling rate is between 0.5K / min-1.5K / min, the opening of the first helium compensation valve is maintained.

9. The deep low temperature environment test method with controllable temperature change rate according to claim 8, characterized in that: If the current pressure is less than or equal to 10 -3 pa, adjust the heating power of the temperature control plate; if the current pressure is greater than 10 -3 When pa, the first helium compensation valve is closed, and the vacuum pump group is used to continue to evacuate the environment simulation container.

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